SERVER-25640 check if jstests leave unterminated processes

3 files changed, 51 insertions, 4 deletions

diff --git a/src/mongo/shell/dbshell.cpp b/src/mongo/shell/dbshell.cpp
index 83e07975a68..fea0aefc995 100644
--- a/src/mongo/shell/dbshell.cpp
+++ b/src/mongo/shell/dbshell.cpp
@@ -930,10 +930,37 @@ int _main(int argc, char* argv[], char** envp) {
             cout << "failed to load: " << shellGlobalParams.files[i] << endl;
             return -3;
         }
-        if (mongo::shell_utils::KillMongoProgramInstances() != EXIT_SUCCESS) {
-            cout << "one more more child processes exited with an error during "
-                 << shellGlobalParams.files[i] << endl;
-            return -3;
+
+        // Check if the process left any running child processes.
+        std::vector<ProcessId> pids = mongo::shell_utils::getRunningMongoChildProcessIds();
+
+        if (!pids.empty()) {
+            cout << "terminating the following processes started by " << shellGlobalParams.files[i]
+                 << ": ";
+            std::copy(pids.begin(), pids.end(), std::ostream_iterator<ProcessId>(cout, " "));
+            cout << endl;
+
+            if (mongo::shell_utils::KillMongoProgramInstances() != EXIT_SUCCESS) {
+                cout << "one more more child processes exited with an error during "
+                     << shellGlobalParams.files[i] << endl;
+                return -3;
+            }
+
+            bool failIfUnterminatedProcesses = false;
+            const StringData code =
+                "function() { return typeof TestData === 'object' && TestData !== null && "
+                "TestData.hasOwnProperty('failIfUnterminatedProcesses') && "
+                "TestData.failIfUnterminatedProcesses; }"_sd;
+            shellMainScope->invokeSafe(code.rawData(), 0, 0);
+            failIfUnterminatedProcesses = shellMainScope->getBoolean("__returnValue");
+
+            if (failIfUnterminatedProcesses) {
+                cout << "exiting with a failure due to unterminated processes" << endl
+                     << "a call to MongoRunner.stopMongod(), ReplSetTest#stopSet(), or "
+                        "ShardingTest#stop() may be missing from the test"
+                     << endl;
+                return -6;
+            }
         }
     }
 
diff --git a/src/mongo/shell/shell_utils_launcher.cpp b/src/mongo/shell/shell_utils_launcher.cpp
index 680a1c235b2..f37f4b6964c 100644
--- a/src/mongo/shell/shell_utils_launcher.cpp
+++ b/src/mongo/shell/shell_utils_launcher.cpp
@@ -1048,6 +1048,23 @@ int KillMongoProgramInstances() {
     return returnCode;
 }
 
+std::vector<ProcessId> getRunningMongoChildProcessIds() {
+    std::vector<ProcessId> registeredPids, outPids;
+    registry.getRegisteredPids(registeredPids);
+    // Only return processes that are still alive. A client may have started a program using a mongo
+    // helper but terminated another way. E.g. if a mongod is started with MongoRunner.startMongod
+    // but exited with db.shutdownServer.
+    std::copy_if(registeredPids.begin(),
+                 registeredPids.end(),
+                 std::back_inserter(outPids),
+                 [](const ProcessId& pid) {
+                     const bool block = false;
+                     bool isDead = wait_for_pid(pid, block);
+                     return !isDead;
+                 });
+    return outPids;
+}
+
 MongoProgramScope::~MongoProgramScope() {
     DESTRUCTOR_GUARD(KillMongoProgramInstances(); ClearRawMongoProgramOutput(BSONObj(), 0);)
 }
diff --git a/src/mongo/shell/shell_utils_launcher.h b/src/mongo/shell/shell_utils_launcher.h
index 0b79180fc19..1a38b21c7b1 100644
--- a/src/mongo/shell/shell_utils_launcher.h
+++ b/src/mongo/shell/shell_utils_launcher.h
@@ -56,6 +56,9 @@ struct MongoProgramScope {
 };
 int KillMongoProgramInstances();
 
+// Returns true if there are running child processes.
+std::vector<ProcessId> getRunningMongoChildProcessIds();
+
 void installShellUtilsLauncher(Scope& scope);
 
 /** Record log lines from concurrent programs.  All public members are thread safe. */